Tag Archives: Icom IC-705 ATU

Antenna Tuners, News, Reviews

Choosing the best Icom IC-705 portable external antenna (ATU)

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I’ve received no less than three inquiries this weekend from readers who are seeking advice about purchasing a portable external ATU to pair with their Icom IC-705 transceiver.

Fortunately, there are few options on the market and I believe there is no “right” one because choices are really based on operator preferences.

I’ll do my best to sum up my thoughts below based on the three ATUs I regularly employ and what we know so far about the AH-705 ATU from Icom.

Keep in mind this list will not include some excellent options from LDG, MFJ, and other companies simply because I haven’t used them in the field. Please feel free to add your comments if you have experience with other good options.

Mat-Tuner mAT-705 Plus

The Mat-Tuner mAT-705 Plus is the first external ATU on the market that directly pairs with the Icom IC-705 via a control cable.

Note that I had issues with the first iteration of the mAT-705 and could not recommend it.

The latest iteration–the mAT-705 Plus–is the ATU I can recommend.

Be careful if purchasing an mAT-705 used as you’ll want to make sure you’re getting the Plus version. The Plus version has a USB-C charging port on the front panel (seen in the photo above)–the original mAT-705 does not (it uses replaceable 9V cells).

Pros:

  • Perfectly pairs with the IC-705 for full CAT control
  • Wide tuning range
  • Tuning is fast and relatively quiet
  • Numerous memories making repeat matching rapid
  • Internal rechargeable battery
  • Rugged chassis

Cons:

  • Cannot be paired with other radios without modification (not recommended by the manufacturer)
  • At $220 US, it’s not the cheapest option
  • Because the IC-705 relies on CAT control for operation, if you leave the control cable at home or on a park bench, you will not be able to operate the ATU. (Pro)Fortunately, the CAT cable is a simple 3 conductor 1/8″ stereo patch cable.
  • Not weather-proof

Click here to see the AH-705 Plus in action and read a deeper review.

Summary: If you’re looking for an ATU to take full advantage of IC-705 CAT control, the mAT-705 Plus is a great option. The only significant disadvantage of this ATU is the fact that it only pairs with the IC-705 (or possibly other Icom transceivers with similar CAT control). In other words, you can’t pair it with other QRP transceivers you might own.

Click here to check out the mAT-705 Plus at Vibroplex, DX Engineering, Wimo, and Mat-Tuner.

Elecraft T1

The Elecraft T1 has been on the market for at least 16 years and is one of the most popular portable antenna tuners on the market.

Elecraft offers the T1 in kit form ($159.95) and factory assembled/tested ($189.95).

The Elecraft T1 has a CAT control port that has been used with the FT-817 in the past. Elecraft recently announced that they will also produce an IC-705 CAT cable that will allow full pairing with the IC-705 transceiver (much like the mAT-705 Plus above). 

To be clear, though, the T1 doesn’t need a control cable to function: simply press the TUNEe button for one second, then key your transceiver.

Pros:

  • Very wide tuning range
  • Soon it will have an IC-705 CAT connection cable option
  • Uses common 9V battery that is easy to replace in the field. (Con) Not internally-rechargeable like the mAT-705 Plus.
  • One of the most compact automatic ATUs on the market
  • Pairs with any 0.5-W to 20-W transceiver covering the 160-6 meter bands
  • FT-817 Remote-Control Option

Cons:

  • Front panel buttons need protection while in your pack to prevent accidental pressing that will deplete the battery. I 3D-printed this simple cover that works brilliantly.
  • Not weather-proof

Summary: The Elecraft T1 is my personal favorite. Since the T1 pairs with any QRP transceiver, I love the flexibility. The T1 has also been on the market for ages and is a solid, safe choice–we know longevity is benchmark. I’ve never been in a situation where the T1 couldn’t find a reasonable match.

I will certainly test the new IC-705 control cable option when it is released in the near future–stay tuned.

Click here to check out the T1 at Elecraft.

Icom AH-705

Photo by Icom Japan

Disclosure: I have not tested the AH-705 yet, but Icom plans to send me one on loan for review once available in North America.

We do know a bit about the AH-705  because Icom has published details/specifications and some users in Japan have already received units from the first production run.

The AH-705 is Icom’s custom ATU designed to perfectly pair with the Icom IC-705 via control cable. If you want an all-Icom setup, this is it.

Pricing in US dollars is TBD at time of posting, but the announced retail price is $350 .

Pros:

  • Perfectly pairs with the IC-705
  • Wide tuning range
  • 2-way power sources using alkaline batteries (2 x AA cells) or external 13.8 V DC
  • IP54 dust-protection and water resistance construction
  • Could (potentially–?) be permanently mounted outdoors at the antenna feed point as a dedicated remote tuner

Cons:

  • In terms of overall size, the AH-705 appears to be the largest of the portable ATUs mentioned here
  • It doesn’t appear AA batteries can be recharged internally
  • The AH-705 may (we don’t know yet) only work with the IC-705 and possibly similar Icom models
  • The maximum power handling of the AH-705 is 10 watts–if you use other transceivers (if that is even possible) you would have to be extremely careful with power settings.
  • The AH-705 is pricey if the actual retail price ends up being near the projected $350 mark. Hopefully, it’ll be much less than this.
  • Like the mAT-705 Plus, the AH-705 will require a control cable for operation. (Pro) Of course this means it pairs perfectly with the IC-705 and can follow frequency changes without RF sensing.

Summary: Keep in mind, I have not tested the AH-705 yet, so this is only based on announced specifications.

The strongest selling point for the AH-705? Since the AH-705 is designed to be dust and weather resistant, it could be mounted at the antenna feed point. At home, perhaps it could act like an externally-mounted, remotely-controlled antenna tuner. I’m not sure what the maximum length of the control cable could be, but Icom Japan even lists a 16 foot control cable as an accessory. Of course, you would still need to follow Icom’s guidance about protecting the antenna, transmitter and control cable connection points.

The biggest negative to me is the size. Just check out how large it is compared to the IC-705 in this video. It’s still very portable, but the other ATU options above are much smaller.

Still: if the AH-705 is great at matching antennas and the price ends up falling below the $300 point, I’m sure it’ll be a very popular ATU.

For more information about the AH-705, check out the product page on Icom Japan’s website. I will test a loaner AH-705 in the field this year.

Emtech ZM-2

Another option often overlooked are portable manual antenna tuners. I’m a big fan of the Emtech ZM-2 which is offered both in kit ($62.50) and factory assembled/tested form ($87.50).

It is a manual tuner, so requires manual input to find a match. While it’s not as easy as push-button tuning, it isn’t complicated either.

Here’s my routine:

  1. I set the top right switch to “GROUND” if using coax feed line and “LINK” if using a balanced line.
  2. Set the added capacitance switch “ADD” to “0”
  3. Set the TUNE/OPERATE switch to OPERATE
  4. I set both capacitors to middle positions (6 on the scale)
  5. Tune to AM or SSB and listen to the noise floor as I tune the variable capacitors to maximize the noise level. I typically start with the left capacitor, maximize it, then maximize the right capacitor
  6. If the antenna is particularly challenging, I might add 250 or 500PF via the ADD switch
  7. Set the TUNE/OPERATE switch to TUNE
  8. In CW mode, I key down and make fine tuning adjustments with the variable capacitors to make the red tuning LED turn off (high SWR makes the red LED illuminate)
  9. Set the TUNE/OPERATE switch to OPERATE and hop on the air! (Often, I’ll double-check the SWR on my transceiver).

This sounds complicated, but once you’ve done it even two or three times, it becomes routine. I’ve yet to find a wire antenna the ZM-2 can’t match–it’s a very capable tuner.

Pros:

  • The most affordable option listed here
  • Very wide matching range
  • Portable and very lightweight
  • Requires no batteries for operation
  • Mechanically simple
  • Reliable

Cons:

  • Although not complicated, there is a small learning curve involved
  • Each time you change bands, you will need to manually re-tune the ZM-2
  • Not as fast and hassle-free as an automatic ATU
  • Not weather-proof

Summary: I carry the ZM-2 with me even if I plan to use an automatic portable antenna tuner. If my auto ATU loses power for some reason, the ZM-2 will always rescue me. Plus, it’s just as capable of making tough matches as the ATUs above.

I also love using the ZM-2 to match antennas for shortwave broadcast listening outside the ham bands.

Even if you buy an automatic ATU, I would still encourage you to buy a ZM-2 as a backup.  It’s affordable, reliable, and very handy.

Click here to check out the Emtech ZM-2.

What are your favorite portable ATUs?

As I mentioned above, these choices are just a small selection of what’s actually available on the market. Please share your favorite portable ATUs and experience by leaving a comment!

Antennas, News, Portable, QRP, Reviews

MAT-TUNER mAT-705 woes

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UPDATE: Mat-Tuner released the latest updated and upgraded version of the mAT-705 in December 2020. It’s called the mAT-705Plus. Click here to read my initial review of the mAT-705Plus. Note that the following article pertains to the original mAT-705 which is no no longer being produced, but still available for sale (at time of posting) both new and used.

Last week, I posted a review of the Mat-Tuner mAT-705 antenna tuner that is designed to pair with the new Icom IC-705 transceiver.

My initial assessment was very positive, but since then the shine has worn off. I’ll explain…

On Monday, I took the IC-705 and mAT-705 to the field for a little Parks On The Air (POTA) fun.

The Par EndFedz EFT-MTR triband (40/30/20M) antenna

Enroute to the site, I thought it would be a good test for the mAT-705 to attempt to tune the excellent EFT-MTR antenna (which is resonant on 40, 30, and 20 meters) on all bands above 40 meters.

After arriving on site, I very quickly deployed the EFT-MTR antenna using my throw line. I then hooked the EFT-MTR up to the mAT-705 ATU and connected the ATU to the IC-705.

After turning on the IC-705, I opened the menu screen and tried to engage the mAT-705 ATU. Unfortunately, the ‘705 didn’t recognize the tuner. I double-checked to make sure the control cable to the mAT-705 was secure–it was. After some head-scratching, I realized I must have left the ATU’s mechanical power switch in the “on” position while using it a few days prior.

This evidently depleted the mAT-705’s internal 9V battery. What a bummer!

I bragged about the mAT-705 in a previous post because, frankly, it is a very capable ATU–quickly finding matches from 160 to 6 meters on my random wire field antenna and horizontal loop antenna at home. It also has an incredibly sturdy aluminum enclosure.  It’s a very capable ATU in terms of quickly and efficiently finding matches and, superficially smacks of superb build quality.

Issues

But if I’m being honest, my love affaire with the mAT-705 ended Monday due to a number of discoveries.

9 volt batteries

The mAT-705 next to the IC-705

According to Mat-Tuner’s product description, the mAT-705:

“[I]s powered by an internal standard 9 volt alkaline battery. Power saving technology inside the tuner allows the use of the unit for months without replacement. No battery power is consumed by the unit when powered off.”

Turns out, they mean it saves power only with the mechanical power switch turned “off.”

This, in turn, means that the user must remember each time they use the mAT-705 to flip the mAT-705 mechanical switch off.  If left in the “on” position by accident, even with no connection to the IC-705 and while not in use, it will deplete a 9V cell in a matter of a few days.

This is a significant issue, in my opinion, and is compounded by a few other design choices:

Complicated battery removal

There is no “easy access” to the mAT-705 battery. The user must use a supplied (standard) Allen wrench and unscrew the rear panel from the chassis.

As we mentioned in our previous post, Mat-Tuner actually has a procedure for opening the case and replacing the 9V battery in order to prevent the LED illuminators from falling out. I followed this procedure to the letter, yet the illuminators still fell out. They simply aren’t secured properly and would be very easy to lose if replacing a battery in the field.

The LED illuminators

Once open, you discover that the 9V battery’s holder is a piece of double-sided tape. Seriously:

The mAT-705’s 9V battery holder

In addition, the ATU board essentially “floats” in the chassis secured in slide-in slots. The problem is the back panel–which you pull to remove the board–is only secured to the ATU board with three wired solder points.

Even when I lay the board down carefully, gravity will bend those BNC connections.

I can’t imagine this holding up with multiple battery replacements.

No external power port

Given that battery removal will take a user at least 5 minutes, I find it a little surprising that there’s no external power port.

It would be no problem at all for me, if the 9V battery died, to simply hook the mAT-705 up to my portable DC distribution panel like I can do with other external ATUs. But since this isn’t an option, you’re simply out of luck in the field. Better carry spare 9V batteries!

Where the lack of an external power port is really an issue, though, is for mAT-705 users in the shack. If the IC-705 becomes one of your main radios, you’ll have to be very disciplined to turn it on and off each time you use it, else you’re going to be replacing a lot of 9V cells.

Command connection to the IC-705 is basic

It seems to me that if you build an antenna tuner specifically to pair with a radio via a dedicated control cable, the tuner could potentially:

  • derive power from the transceiver
  • or at least be told by the transceiver to turn completely off when not actively in use. Especially since once a match is found, it’s locked into position even if the mAT-705 has no power.

The mAT-705 can’t do either.

Is it a good ATU? Yes. But inside it could be better.

As I said above, my original review stands in terms of the mAT-705’s ability to match antennas, I think it’s brilliant.

But I can no longer recommend the mAT-705 until some of these design shortcomings are addressed.

I’ve never owned a portable ATU that required so much discipline from the user in order to preserve the battery. I’ve also never owned one that was so fragile internally. Most portable ATUs *only* turn on when finding a match and then either “sleep” or turn off when not in use.

And portable ATUs like the Elecraft T1, for example? Even have a convenient battery compartment for easy removal. (And, oh yeah, the T1 will run ages on a 9V!)

The Elecraft T1 ATU 9V battery compartment

To add insult to injury, it’s one thing to discover that your mAT-705 ATU eats 9V batteries if left on but not in use, but it’s quite something else to discover your $220 ATU’s 9V battery is held in with a piece of double-sided sticky tape.

How long could this possibly function if you’re replacing batteries frequently in the field?

My hope is that Mat-Tuner will sort out this design and re-introduce the mAT-705 to the market. I’ve heard so many positive things about other Mat-Tuner models which is why I wanted to try one out with the IC-705.

Mat-Tuner ATUs are sold by respected retailers in the ham radio world (like Vibroplex, who loaned this model for review) so I expect they’ll address these concerns in the coming months. I’ll certainly post all updates here on QRPer.

Until then, I have to recommend skipping the $220 mAT-705 and instead purchasing the excellent ($160 kit/$190 assembled) Elecraft T1.